Abstract: In an immediate hot water supply operation mode in which a circulation pump is activated while a hot water supply faucet is closed, a water heating apparatus forms an immediate hot water supply circulation path by an inner path including a water entry path, a heat exchanger, and a hot water output path and an outer path bypassing the hot water supply faucet, as being combined. A controller stores as an actual flow rate value for each immediate hot water supply operation mode, a flow rate detection value by a flow rate sensor at predetermined timing, and calculates a flow rate learning value based on a plurality of stored actual flow rate values. When the flow rate detection value becomes larger than a criterion value set in accordance with the flow rate learning value, use of the hot water supply faucet is detected and the circulation pump is deactivated.

Abstract: A hot water supply device including an inlet pipe, an outlet pipe, a burner unit, a heat exchanger, an exhaust aperture, a first temperature sensor detecting a measured exhaust temperature of the exhaust gas, a second temperature sensor detecting a water temperature of water entering the inlet pipe, and a processor. The processor is configured to obtain an error between the measured exhaust temperature and an estimated exhaust temperature, and detects that scale clogging has occurred inside the heat exchange tubing based on an index which is generated using the error between the measured exhaust temperature and the estimated exhaust temperature. The estimated exhaust temperature is a first predetermined value that is determined using a numerical equation which has at least the water temperature of water entering the inlet pipe and a scale number of the hot water supply device as variables of the numerical equation.

Abstract: The disclosure provides a combustion device for burning LP gas filled in a gas cylinder as fuel in a combustion unit. The combustion device includes: a control unit for controlling a combustion operation based on a preset operation table such that a combustion output reaches a target output, and an output detection part for detecting the combustion output. In a case where the combustion output detected by the output detection part is risen by a reference value or more relative to the target output, the control unit notifies of a lowering in the remaining amount of LP gas in the gas cylinder.

Abstract: The disclosure includes a hot water circulation device, and a hot water device monitoring system including a circulation passage; a circulation pump circulating hot water in the circulation passage; a closed expansion tank in which a water chamber communicating with the circulation passage and an air chamber filled with a predetermined pressure in initial state are partitioned by a diaphragm; and a control unit controlling hot water circulation. The hot water circulation device includes an air chamber pressure sensor detecting pressure in the air chamber; a closing valve cutting off water chamber from the circulation passage; and an open valve opening to atmosphere from between closing valve and water chamber. The control unit closes closing valve and opens opening valve during hot water circulation, detects pressure in the air chamber by the air chamber pressure sensor, and issues a warning notification when the pressure is not within predetermined pressure range.

Abstract: The disclosure provides a water heater. The water heater includes a water heater main body portion including a heat exchanger and a combustion device; a fan and a motor for driving the fan; an exterior case; and an air supply adapter mounted to an upper wall portion of the exterior case. The combustion device and the motor are positioned in a region near an upper portion within the exterior case. The combustion device is at least partly positioned between the air supply adapter and the fan in a plan view. An air outlet of the air supply adapter opens substantially horizontally, avoiding a direction directly facing the motor. The air flowing out from the air outlet is changed in direction by a side wall portion of the exterior case and flows to reach a portion of the motor.

Abstract: A premixing flow path forming member of a premixing device includes a member whose attachment mode can be changed, and flow path resistance of a fuel gas flow path can be changed when the attachment mode of the member is changed.

Abstract: A connected-type hot-water supply system includes hot-water supply apparatuses connected in parallel and a control means. The control means sets one main hot-water supply apparatus and sub-hot-water supply apparatuses, and performs leveling control of cumulative loads of the hot-water supply apparatuses by setting the main hot-water supply apparatus based on sequential rotation among the hot-water supply apparatuses. The control means includes a failure sign response mode in which it is determined whether there is a failure sign respectively for components of the hot-water supply apparatuses, and when a component of a part of hot-water supply apparatuses is a failure sign component determined to have a failure sign, a main use time of a hot-water supply apparatus having the failure sign component is increased, and the main use time is a main use time of serving as the main hot-water supply apparatus in the leveling control.

Abstract: A heat exchanger includes: a casing into which heating gas is supplied; and a plurality of heat transfer tubes which are arranged in the casing, wherein the plurality of heat transfer tubes are set in a posture in which a plurality of straight tube portions are arranged in a direction intersecting a heating gas flow direction, are stacked a plurality of stages in the heating gas flow direction, and are distinguished into first and second heat transfer tubes respectively located on an upstream side and a downstream side in the heating gas flow direction, and wherein the second heat transfer tube is formed so that an outer diameter of the tube and an arrangement pitch of the plurality of straight tube portions are smaller than those of the first heat transfer tube.

Abstract: A premixing device includes: a gas flow path for allowing air to flow; a gas outlet that allows fuel gas to flow out into the gas flow path by utilizing a negative pressure; and a flapper disposed in the gas flow path. The premixing device further includes an operation regulating part for the flapper which allows the opening degree of the flapper to change according to the air flow rate in a range below a predetermined upper limit position while preventing the flapper from rotating in an opening direction beyond the upper limit position. The operation regulating part is capable of selectively switching and setting one of a first upper limit position for normal combustion and a second upper limit position for fuel ignition. The opening degree of the flapper at the second upper limit position is smaller than that at the first upper limit position.

Abstract: A hot water supplier includes a combustion unit including multiple combustion stages; a combustion fan supplying combustion air; a fuel supply unit supplying fuel; a heat exchange unit; a water supply unit supplying hot water to heat exchange unit; a hot water tapping unit discharging hot water heated in heat exchange unit by using combustion heat obtained by burning fuel in combustion unit; and a control unit controlling heating operation. When reheating operation is allowed in which hot water from hot water tapping unit is returned to water supply unit and reheated by heat exchange unit, control unit stores heating time using only a combustion stage having minimum combustion capacity during reheating operation as time data. If this time data tends to increase over time, deterioration progress of a heat retaining material covering a hot water pipe to which hot water is supplied from hot water tapping unit is determined.

Abstract: A hot water supplier monitoring system includes a monitoring server monitoring hot water suppliers via a communication network. The hot water supplier supplies hot water by adjusting temperature of hot water heated by a heat exchange unit using combustion heat from combustion operation. The monitoring server accumulates operation data of combustion operation transmitted from the suppliers, and predicts and notifies malfunction occurrence for each supplier based on trend of change in the data over time. The data includes number of flame quenchings of the combustion unit in combustion operation. The monitoring server divides the suppliers into groups according to installation areas, compares the number of quenchings of same period among the groups, compares with previous number of quenchings of same group, and, for a specific group determined having an abnormal number of quenchings, excludes the data determined having an abnormal number of quenchings and predicts malfunction occurrence for each supplier.

Abstract: A hot-water supply system (1) remotely controls, via a server (50) and using a portable terminal device (30), a hot-water supply device (10) connectable to an external communication network (40). The hot-water supply system (1) is provided with a control unit which performs a notification process for notifying at least another, already-associated portable terminal device (30) that the portable terminal device (30) for performing remote control has been newly associated with the hot-water supply device (10). For example, a control unit of the server (50) performs the notification process as the control unit.

Abstract: An operation apparatus monitoring system includes an operation apparatus as a monitoring target. The operation apparatus includes a control part capable of executing control of acquiring multiple pieces of apparatus information associated with an operation status and periodically transmitting acquired data of the multiple pieces of apparatus information to a monitoring apparatus. In the control part, multiple groups are set, and data of the multiple pieces of apparatus information are grouped to belong to at least one of the multiple groups and are stored. Transmission of data of the multiple pieces of apparatus information to the monitoring apparatus is executed according to a sequence of data transmission to the monitoring apparatus determined for each group.

Abstract: Provided is a method for manufacturing an exterior case for a hot-water unit, used to house hot-water equipment for generating or storing hot water inside. The method includes a step combining an inkjet printing step for forming an inkjet printing layer by applying inkjet printing to the outer surface of a component of the exterior case and a curing step for curing the inkjet printing layer, in which the inkjet printing step and the curing step are repeated a plurality of times at the same location to form a thick printing portion in which the plurality of inkjet printing layers are laminated in an overlaid state.

Abstract: A heat exchanger includes: a case which has a first side wall that stands upright in a vertical height direction and to which a heating medium is supplied inside; and heat transfer tubes for heating hot water housed in the case. Two end portions of the heat transfer tubes in a longitudinal direction are joined to the first side wall via brazing portions, and the heat transfer tubes are supported by the first side wall. The heat exchanger further includes heat transfer tube support portions provided on the first side wall for supporting portions of the heat transfer tubes near the first side wall to prevent the portions of the heat transfer tubes near the first side wall from descending below a first predetermined height.

Abstract: A heating and hot water supply system, including: a combustion unit combusting a fuel to generate a combustion gas; a heat exchange unit heating a heat medium and hot water according to heat exchange with the combustion gas; an exhaust unit that exhausting the combustion gas after heat exchange. The heat exchange unit includes a plate type heat exchanger by laminating vertically-upright rectangular plates with gaps, and is configured to heat the heat medium by causing the combustion gas and the heat medium to alternately flow through the gaps. An inlet for the heat medium is provided at lower corner of the plate type heat exchanger, a discharge opening for the heat medium is provided at upper corner farthest from the inlet, and a hot water passage through which hot water flows in the plate type heat exchanger is provided at upper corner above the inlet.

Abstract: A heating and hot water supply system includes: a combustion means; a heat exchanger; a heating terminal; a circulation passage that connects the heat exchanger and the heating terminal; a circulation means; a bypass passage branched from the circulation passage and bypassing the heating terminal; a distribution means for distributing a heating medium to the circulation passage and the bypass passage; a hot water supply heat exchanger for the bypass passage; and a hot water supply passage; wherein the distribution means can adjust the distribution ratio so as to correspond to a heating operation, a hot water supply operation, and a simultaneous heating and hot water supply operation, and when the distribution ratio on the circulation passage side of the distribution means is smaller than a prescribed value during the simultaneous heating and hot water supply operation, the blowing operation of the blower at the heating terminal is prohibited.

Abstract: Provided is an exterior case for a hot-water unit, used to house hot-water equipment for generating or storing hot water inside, includes a thick printing portion that is provided on the outer surface of the exterior case and in which a plurality of inkjet printing layers are laminated in an overlaid state. It may be configured with thick printing portions that constitute Braille.

Abstract: An exhaust adapter includes a cylindrical part for connecting an exhaust pipe of a combustion device to a collective exhaust duct; and a backflow prevention structure for preventing backflow of the exhaust from the collective exhaust duct side to the exhaust pipe side. The backflow prevention structure includes: a damper receiving part formed with an opening through which the exhaust from the exhaust pipe passes; an exhaust damper plate that opens the opening by pressure of the exhaust from the exhaust pipe and closes the opening by its own weight when there is no exhaust from the exhaust pipe; a support shaft that rotatably supports the exhaust damper plate; and a bearing part that supports the support shaft. A pair of shaft hole parts of the exhaust damper plate for inserting the support shaft is formed in a long hole shape.

Abstract: The disclosure provides a collective exhaust system capable of safely detecting a closing failure of a check valve of the collective exhaust system. The collective exhaust system includes: multiple combustion devices including blowing parts and exhaust pipes; a collective exhaust duct to which the exhaust pipes of the multiple combustion devices are respectively connected; and check valves respectively provided between the exhaust pipes and the collective exhaust duct. The collective exhaust system is configured to detect a closing failure of the check valves by performing, in a state where one of the blowing parts of the multiple combustion devices is stopped and all the other blowing parts are driven with a predetermined blower capacity, a backflow determination from the collective exhaust duct to the combustion device with the stopped blowing part, and by performing the backflow determination for the multiple combustion devices.